Handbook of Energy Storage for Transmission or ... - W2agz.com

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This site was selected so that power from the flywheel equipment may be utilized to
support performance testing of new technology trains on the test track. Testing requires a
stable track voltage, which has not been available at this site. As shown in Figure 16
average voltage is approximately 672 Vdc at light load, however excursions well above
and below this level are were common during train operations. The existing substation
spacing along the Far Rockaway Line at Broad Channel makes the voltage requirements
for performance testing (600V maintained) difficult to meet.
Figure 16
Typical Voltage Profile At The Far Rockaway Test Track In October 2001
The prototype installation consists of ten individual high-speed flywheels of 100-kw
each, connected together to provide one-megawatt capacity, see photo in Figure 17.
Together the flywheels store about 5 kWh in kinetic energy and could be expected to
operate as often as every 2 minutes during peak hours, and average about every 6 minutes
during normal operating hours. A complete cycle of the flywheels consist of a 20 second
discharge triggered by reduced voltage during train accelerations and a recharge at
approximately the same rate if trains are regeneratively braking in the vicinity.
Otherwise the recharge is controlled based on track voltage during the several minutes
between trains.
Figure 17
Flywheel Installation At NYCT Bay Equalizer Location, 10 1-MW Units In New Building
Flywheels Page 31